[ath9k-devel] Can't associate with a particular AP

[Julien Valroff <julien@kirya.net>]

Hi,

Le dimanche 16 oct. 2011 ? 17:31:44 (+0200 CEST), Adrian Chadd a ?crit?:
> Can you please grab a third device and grab a dump of the actual
> probe/association frames?
> 
> I think it'd be helpful to see what's changed.

I have tried and captured the association process from my 2 other laptops
using wireshark, but unfortunately, I am unable to capture packets in
monitoring mode: in Wireshark, the box is not greyed out, but I cannot tick
it.

I've tried reading the Wireshark documentation on this point, but I could
not see anything about this problem.

I have followed Peter's instructions and the ones described in [0] both
with the same results.

But still, I have been able to capture something from the problematic
laptop, you will find the wireshark logs attached.

When failing to associate, I can see a lot of lines as follows:
50	11.081661	ba:f4:8a:c6:c8:44 (TA)	74:2f:68:57:2c:dc (RA)	802.11	46	Request-to-send, Flags=........C

followed by:
166	23.082827	ba:f4:8a:c6:c8:44	74:2f:68:57:2c:dc	802.11	56	Deauthentication, SN=1142, FN=0, Flags=........C

where:
ba:f4:8a:c6:c8:44 is my AP
74:2f:68:57:2c:dc is my Atheros wlan NIC

When the association succeeds, I notice the MAC address of the AP changes:
99	5.752088	c6:6e:27:a6:be:a4	74:2f:68:57:2c:dc	802.11	272	Probe Response, SN=269, FN=0, Flags=........C, BI=100, SSID=Kirya
                      ^^^^

Which is confirmed by iwlist scan.
Before the association:
Cell 01 - Address: BA:F4:8A:C6:C8:44
        Channel:3
        Frequency:2.422 GHz (Channel 3)
        Quality=26/70  Signal level=-84 dBm  
        Encryption key:on
        ESSID:"Kirya"

After the succeeded association:
Cell 04 - Address: C6:6E:27:A6:BE:A4
        Channel:3
        Frequency:2.422 GHz (Channel 3)
        Quality=70/70  Signal level=-35 dBm  
        Encryption key:on
        ESSID:"Kirya"

How is this possible?

Please continue and CC me as I am not subscribed to the list.

Cheers,
Julien

[0] http://wiki.wireshark.org/CaptureSetup/WLAN#Linux

-- 
  .''`.   Julien Valroff ~ <julien@kirya.net> ~ <julien@debian.org>    
 : :'  :  Debian Developer & Free software contributor
 `. `'`   http://www.kirya.net/
   `-     4096R/ E1D8 5796 8214 4687 E416  948C 859F EF67 258E 26B1
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